Apparently CM Stacker 830 and the Evolution version have some differences.
Newegg review posts:
"What is the difference between CM Stacker 830 and CM 830 Evolution? Please see the list below: Model Number ? RC-830-SSN1 -> RC-830-SSN2-GP RC-830-KKN1-GP -> RC-830-KKN2-GP Changes: 1) Supports EPS PSU (230mm length) 2) Includes Wheels 3) Includes Clear Cover HDD for (Western Digital Raptor X hard drive) 4) Added bottom air inlet 5) Paint quality problem in top panel issue has been solved 6) Fixed the VGA card installation problem issue 7) Increased firewire cable length from 750mm to 900mm 8) Solve problem of installation for side panel 9) Solve problem for FDD bracket without screw thread"